As Ebola outbreak rages, vaccine is 97.5% effective, protecting over 90K people
arstechnica.com
arstechnica.com
As little as 5 years ago (2014 outbreak is deadliest occurrence), it was difficult to contain and spreading rapidly, it took significant travel limitations to contain it.
I think they might be against it for animistic reasons.
This took a few reads for me to get right